Is a birth certificate really a bond?

You hear a lot of wacky things along those lines and they are all true, even if only in a manner of speaking. The nation's money is officially backed by "full faith and credit". Faith means it's good as long as you believe it's good, and credit means the government's ability to extract taxes from citizens. Your birth certificate identifies you as a citizen, so when you get money, you are being paid with a claim on your own labor. That meets the definition of a bond, and it could also be called a few other things.